Frozen synapse runs fine if I start it up and then play it but if at any point I alt tab out or another window pops up, Frozen Synapse stops responding. I can switch back to it and leave it for around a minute and it will then continue working again though. I'd like to be able to play the game and be able to alt tab (especially when playing against others and waiting for them to complete their turn).

I've been having a similar problem, Frozen Synapse/OpenAL seem to disagree with my usb DAC and seem to want to reload every time I come back to the window, causing the game to hang. You can stop this by typing OpenAlShutdownDriver in the console, but it stops the game from having sound. Not a great solution but it makes the game playable.